Systems and methods for percutaneous body lumen drainage

ABSTRACT

The present disclosure relates generally to the field of devices and procedures for placement of a medical device between adjacent tissue structures. In particular, the present disclosure relates to systems and methods for percutaneous placement of a drainage stent between the gallbladder and gastric lumen (e.g., cholecystogastrostomy), or gallbladder and duodenum (cholecystoduodenostomy).

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of and claims the benefit of theearlier filing date of U.S. patent application Ser. No. 15/944,185,filed on Apr. 3, 2018, which claims the benefit of priority under 35U.S.C. § 119 to U.S. Provisional Patent Application Ser. No. 62/481,621,filed on Apr. 4, 2017, all of which disclosures are hereby incorporatedby reference herein in their entireties and for all purposes.

FIELD

The present disclosure relates generally to the field of medical devicesand establishing fluid communication between body lumens. In particular,the present disclosure relates to systems and methods for percutaneousplacement of a medical device between lumen structures, such as a stentbetween the gallbladder and the stomach or duodenum to facilitatedrainage therebetween.

BACKGROUND

The desire to establish access to body lumens to create fluidcommunication from one to the other is present under variouscircumstances and conditions, such as the desire to establish accessfrom a diseased body lumen to another body lumen to facilitate drainageas an alternative to draining the diseased body lumen along a path to alocation external of a patient's body.

As an example, inflammation of the gallbladder (e.g., cholecystitis) istypically caused by gallstones that block the release of bile into thedigestive system, and may result in episodic or continual discomfort tothe patient. Although a preferred treatment for cholecystitis issurgical removal of the gallbladder (e.g., cholecystectomy), patientswho are poorly suited for open or laparoscopic surgical intervention mayrequire an alternative interventional radiology (IR) procedure to drainthe gallbladder. An exemplary IR procedure involves draining thegallbladder outside the body (e.g., collection bag, etc.) through apercutaneously implanted tube. Although this procedure is relativelystraightforward and widely accessible, the external drain tends to beuncomfortable and may become dislodged and/or infected, requiringadditional surgical intervention and possibly leading to formation of apermanent fistula. Endoscopic (e.g., transmural or transpapillary)gallbladder drainage procedures may address some of the problemsassociated with external drainage tubes. However, institutions may lackthe necessary medical equipment and/or trained personnel required toperform such procedures, e.g., endoscopic ultrasound (EUS) procedures.

A variety of advantageous medical outcomes may therefore be realized bythe systems and/or methods of the present disclosure, which allow thepercutaneous placement of a medical device between body lumenstructures.

SUMMARY

In one aspect, the present disclosure relates to a method comprisingadvancing a hollow needle percutaneously through a second body lumen anda tissue wall of a first body lumen, such that a distal end of theneedle is disposed within the first body lumen, advancing a guidewirethrough the needle into the first body lumen, removing the needle fromover the guidewire, advancing a delivery system for a stent loadedthereon over the guidewire such that a distal end of the delivery systemis disposed within the first body lumen and deploying the stent from thedelivery system to establish fluid communication between the first bodylumen and the second body lumen. In addition, or alternatively, a sheathmay be advanced over the guidewire such that a distal end of the sheathis disposed within the first body lumen. The delivery system may beloaded over the guidewire and through the sheath. The hollow needle mayinclude a trocar with a sharpened tip and an obturator (or stylet)inserted therethrough. The obturator may be removed from the trocarprior to advancing the guidewire through the trocar. The delivery systemmay include an inner member with a lumen therethrough to receive theguidewire, and an outer member disposed coaxially about the innermember, whereby the stent may be loaded on the delivery system betweenthe inner member and the outer member. The deploying step may includeexposing a distal portion of the stent from within the delivery system,such that the distal portion forms a distal flange of the stent withinthe first body lumen. The deploying step may further include retractingthe delivery system to place the distal flange of the stent in contactwith an inner surface of the tissue wall. The deploying step may furtherinclude retracting the delivery system such that the distal end of thedelivery system is disposed within the second body lumen. The deployingstep may further include exposing a proximal portion of the stent fromwithin the delivery system, such that the proximal portion forms aproximal flange of the stent within the second body lumen. The needlemay be advanced through a portion of the liver prior to the second bodylumen. The needle may be advanced through a portion of the peritonealcavity prior to the second body lumen. The needle may be advancedthrough a body lumen that is not the first or second body lumen prior tobeing advanced through the second body lumen. The second body lumen maybe the gallbladder. The tissue wall may be the gastric wall and thefirst body lumen may be the stomach. The tissue wall may be the duodenalwall and the first body lumen may be the duodenum. The tissue wall maybe the jejunum wall and the first body lumen may be the jejunum. Thesecond body lumen may be the stomach. The tissue wall may be theduodenal wall and the first body lumen may be the duodenum. The tissuewall may be the jejunum wall and the first body lumen may be thejejunum. The tissue wall may be the ileum wall and the first body lumenmay be the ileum. The second body lumen may be the common biliary duct(CBD), the tissue wall may be the duodenal wall and the first body lumenmay be the duodenum. The second body lumen may be a portion of theintestine, the tissue wall may be the wall of a second portion ofintestine and the first body lumen may be the second portion ofintestine. The second body lumen may be a pseudocyst or an abscess, andthe tissue wall and the first body lumen may be the duodenal wall andduodenum or the gastric wall and stomach. Each step of the method may beperformed under at least ultrasonic guidance. Each step of the methodmay be performed under at least fluoroscopic guidance. Each step of themethod may be performed under ultrasonic guidance and fluoroscopicguidance. The steps of the method may be performed laparoscopically.

In another aspect, the present disclosure relates to a method comprisingadvancing a needle percutaneously to establish an access path through asecond body lumen and a tissue wall of a first body lumen, such that adistal end of the needle reaches an interior of a first body lumen,advancing a guidewire along the access path to the first body lumeninterior, advancing a delivery system for a stent having distal andproximal flanges over the guidewire to the first body lumen interior anddelivering the stent from the delivery system, such that the distalflange of the stent is deployed in the interior of the first body lumenand the proximal flange of the stent is deployed in the second bodylumen. The distal flange may engage a distal face of the tissue wall andthe proximal flange may engage an interior wall of the second bodylumen. After the delivery step, the first and second body lumens may beapposed and in fluid communication with each other. After the deliverystep, drainage may be established through the stent from the second bodylumen to the first body lumen. In addition to drainage, thecommunications may connect structures to allow passage of a variety ofmaterials from one to the other, including but not limited to stones,food, passage of medical devices into difficult to reach regions of thebody. The stent may include a covering around and along the stentbetween the proximal and distal flanges. The second body lumen may bethe gallbladder. The tissue wall may be the gastric wall and the firstbody lumen may be the stomach. The tissue wall may be the duodenal walland the first body lumen may be the duodenum. The tissue wall may be thejejunum wall and the first body lumen may be the jejunum. The secondbody lumen may be the stomach. The tissue wall may be the duodenal walland the first body lumen may be the duodenum. The tissue wall may be thejejunum wall and the first body lumen may be the jejunum. The tissuewall may be the ileum wall and the first body lumen may be the ileum.The second body lumen may be the common biliary duct (CBD), the tissuewall may be the duodenal wall and the first body lumen may be theduodenum. The second body lumen may be a portion of the intestine, thetissue wall may be the wall of a second portion of intestine and thefirst body lumen may be the second portion of intestine. The second bodylumen may be a pseudocyst or an abscess, and the tissue wall and thefirst body lumen may be the duodenal wall and duodenum or the gastricwall and stomach. Each step of the method may be performed under atleast ultrasonic guidance. Each step of the method may be performedunder at least fluoroscopic guidance. The method may be performed underultrasonic guidance and fluoroscopic guidance. The steps of the methodmay be performed laparoscopically.

In yet another aspect, the present disclosure relates to a methodcomprising establishing a percutaneous path of access to a first bodylumen through a second body lumen, delivering a stent having distal andproximal flanges (when expanded) along the path to the first body lumen,deploying the distal flange of the stent against a wall of the firstbody lumen within the first body lumen, pulling the distal flange backalong the path to hold the wall of the first body lumen in apposition toa wall of the second body lumen and deploying the proximal flange of thestent against the wall of the second body lumen within the second bodylumen. After the stent is fully deployed, drainage may be establishedthrough the stent from the second body lumen to the first body lumen. Inaddition to drainage, the communications may connect structures to allowpassage of a variety of materials from one to the other, including butnot limited to stones, food, passage of medical devices into difficultto reach regions of the body. The first body lumen may be the stomach orduodenum and the second body lumen may the gallbladder. The percutaneouspath may pass through a portion of the liver prior to the second bodylumen. The percutaneous access path may be established by advancing aneedle directly through a skin layer. The stent may include a coveringaround and along the stent between the proximal and distal flanges. Thesecond body lumen may be the gallbladder. The tissue wall may be thegastric wall and the first body lumen may be the stomach. The tissuewall may be the duodenal wall and the first body lumen may be theduodenum. The tissue wall may be the jejunum wall and the first bodylumen may be the jejunum. The second body lumen may be the stomach, thetissue wall may be the duodenal wall and the first body lumen may be theduodenum. The tissue wall may be the jejunum wall and the first bodylumen may be the jejunum. The tissue wall may be the ileum wall and thefirst body lumen may be the ileum. The second body lumen may be thecommon biliary duct (CBD), the tissue wall may be the duodenal wall andthe first body lumen may be the duodenum. The second body lumen may be aportion of the intestine, the tissue wall may be the wall of a secondportion of intestine and the first body lumen may be the second portionof intestine. The second body lumen may be a pseudocyst or an abscess,and the tissue wall and the first body lumen may be the duodenal walland duodenum or the gastric wall and stomach. Each step of the methodmay be performed under at least ultrasonic guidance. Each step of themethod may be performed under at least fluoroscopic guidance. The methodmay be performed under ultrasonic guidance and fluoroscopic guidance.The steps of the method may be performed laparoscopically.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting embodiments of the present disclosure are described by wayof example with reference to the accompanying figures, which areschematic and not intended to be drawn to scale. In the figures, eachidentical or nearly identical component illustrated is typicallyrepresented by a single numeral. For purposes of clarity, not everycomponent is labeled in every figure, nor is every component of eachembodiment shown where illustration is not necessary to allow those ofordinary skill in the art to understand the disclosure. In the figures:

FIGS. 1, 2A, 2B, 3-5, 6A, 6B, and 7 illustrate exemplary steps forpercutaneous placement of a medical device, according to embodiments ofthe present disclosure.

FIGS. 8A-8D illustrate cross-sections of exemplary stents for use inmethods, according to embodiments of the present disclosure.

FIGS. 9A-9G illustrate cross-sections of exemplary stents for use inmethods, according to embodiments of the present disclosure.

FIGS. 10A-10J illustrate cross-sections of exemplary stents for use inmethods, according to embodiments of the present disclosure.

DETAILED DESCRIPTION

The present disclosure is not limited to the particular embodimentsdescribed herein. The terminology used herein is for the purpose ofdescribing particular embodiments only, and is not intended to belimiting beyond the scope of the appended claims. Unless otherwisedefined, all technical terms used herein have the same meaning ascommonly understood by one of ordinary skill in the art to which thedisclosure belongs.

Although embodiments of the present disclosure are described withspecific reference to systems and methods for placing a drainage stentbetween the gallbladder and the stomach (e.g., cholecystogastrostomy) orduodenum (e.g., cholecystoduodenostomy) without EUS guidance, it shouldbe appreciated that such systems and methods may be used in a variety ofmedical procedures (e.g., external biliary drain conversion,enteroenterostomy, gastrojejunostomy, gastroduodenostomy andgastroileostomy, etc.) to establish and/or maintain a temporary orpermanent open flow passage between a variety of body organs, lumens andspaces (e.g., the dermis, bladder, kidneys, walled-off pancreaticnecrosis (WOPN), pseudocysts, abscesses, etc.) using a variety ofimaging modalities. Moreover, the medical devices disclosed herein arenot limited to drainage stents, but may include medical devicesconfigured to facilitate access to organs or lumens for other purposes,such as removing obstruction and delivering therapy, includingnon-invasive manipulation of the tissue within the organ or lumen and/orthe introduction of pharmacological agents via the open flow passage.

As used herein, the singular forms “a,” “an,” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” or “includes” and/or “including” when used herein,specify the presence of stated features, regions, steps elements and/orcomponents, but do not preclude the presence or addition of one or moreother features, regions, integers, steps, operations, elements,components and/or groups thereof.

As used herein, the term “distal” refers to the end farthest away fromthe medical professional when introducing a device into a patient, whilethe term “proximal” refers to the end closest to the medicalprofessional when introducing a device into a patient.

In various embodiments, the present disclosure relates to a percutaneousmethod for creating an open flow passage between two or more structures(e.g., a first body lumen and a second body lumen). Percutaneous caninclude access directly through a skin layer or laparoscopically througha port. The procedures may be performed with ultrasound guidance, e.g.,transabdominal ultrasound, or fluoroscopic guidance or some combinationof the two.

Referring to FIG. 1, in a first step of a percutaneous method accordingto the present disclosure, the patient may be placed on an operatingtable in a supine position, and the table tilted to place the gastricantrum in a dependent position. Alternatively, the patient may be placedin a position other than supine, e.g., on their left or right side. Anappropriate volume of saline (e.g., approximately 500 cc) may then beintroduced into the stomach, e.g., through a nasogastric tube, to removeopen spaces or air pockets that might attenuate propagation ofultrasound energy. An 18-gauge hollow needle 110 (e.g., trocar withobturator, or needle with stylet) may then be percutaneously advancedunder ultrasound guidance through a dermal layer (e.g., skin) 101 and asection of the liver parenchyma 103 into the gallbladder 105 (e.g.,second body lumen). The liver parenchyma at the needle puncture site maypreferably include a thickness of about 0.50 cm to about 2.00 cm toprevent deflation of the adjacent gallbladder upon penetration by theneedle. In addition to supporting the punctured gallbladder, the spongyconsistency of the liver parenchyma may provide a seal around the needle110 to prevent leakage of the gallbladder contents into the pleuralspace.

Referring to FIGS. 2A and 2B, the needle 110 may be further advancedthrough the gastric wall 107 (e.g., first tissue wall) and into thestomach 109 (e.g., first body lumen) under ultrasound (FIG. 2A) and/orfluoroscopic (FIG. 2B) guidance. In various embodiments, the needle 110may be advanced through the second body lumen, first tissue wall andfirst body lumen without penetrating any portion of the liver.

Referring to FIG. 3, the trocar obturator or stylet (not shown), whendisposed within the hollow needle, may then be removed from the needleand a guidewire 120 advanced through the hollow needle into the stomach109 under fluoroscopic guidance. A sufficient amount of the guidewire120 may be advanced through the hollow needle to form a loop within thestomach 109 to maintain the proper location of the guidewire 120throughout the medical procedure. The hollow needle may then beretracted over the guidewire 120, and a sheath 130 (e.g., 12-French)advanced over the guidewire 120 under fluoroscopic guidance to positiona distal end 132 of the sheath within the stomach 109. A stent deliverysystem 140 may then be advanced over the guidewire 120 through thesheath 130 under fluoroscopic (FIG. 3) and/or ultrasonic (not shown)guidance such that a distal end of the stent delivery system 140 ispositioned within the stomach 109. The stent delivery system 140 mayinclude an inner member with a lumen extending therethrough to receivethe guidewire 120, and an outer member disposed coaxially around theinner member. A drainage stent 150 may be loaded on the stent deliverysystem 140 in a collapsed or non-expanded configuration between theinner and outer member. A distal portion of the drainage stent 150 maybe exposed from within the stent delivery system 140, such that thedistal portion forms a distal flange 152 of the stent 150 within thestomach 109. In various embodiments, the stent delivery system may beadvanced over the guidewire in the absence of a sheath.

Referring to FIGS. 4-5, the stent delivery system 140 and sheath 130 maybe proximally retracted (e.g., pulled) under fluoroscopic (FIG. 4) orultrasonic (FIG. 5) guidance to place the distal flange 152 of the stent150 in contact with an inner surface of the stomach 109.

Referring to FIGS. 6A-6B, the sheath 130 and stent delivery system 140may be further proximally retracted under ultrasonic (FIG. 6A) and/orfluoroscopic (FIG. 6B) guidance to position their respective distal ends132, 142 within the gallbladder 105. In one embodiment, a biologicallyinert fluid (e.g., water, normal saline, dextrose 5% water, etc.) may beinjected into the gallbladder 105 through the sheath 130 to distend thegallbladder and/or provide an improved ultrasonic image. Still usingultrasonic and/or fluoroscopic guidance, a proximal portion of thedrainage stent 150 may be exposed from within stent delivery system 140,such that the proximal portion forms a proximal flange 154 of the stent150 within the gallbladder 105, thereby providing an open flow path oraccess path between the gallbladder and stomach.

Referring to FIG. 7, with the drainage stent 150 properly deployed, thestent delivery system 140 may be removed over the guidewire 120 andthrough the sheath 130. The sheath and guidewire may then also beremoved from the patient. Depending on the individual patient'spost-operative health (e.g., if the gallbladder drainage procedure hasalleviated all or some of their symptoms), the drainage stent may beremoved after approximately 4-6 weeks by an EUS procedure, or underdirect visualization (e.g., through an endoscope, gastroscope, orduodenal scope, etc.).

In certain medical procedures, the stomach may represent the preferredlumen for gallbladder drainage due to the relatively robust nature ofthe gastric wall. For example, the gastric wall may resist abrasion orperforations caused by contact with the drainage stent, and/or be moreamenable to receiving sutures or staples to close the anastomosisfollowing removal of the drainage stent. In certain other medicalprocedures, the duodenum may represent the preferred lumen forgallbladder drainage. For example, although the tissue wall of theduodenum tends to be less robust than the gastric wall, the shorterdistance between the gallbladder and duodenum may allow the deployeddrainage stent to exert less force on or between the tissue walls.Pre-procedure imaging of the patient's anatomy may be used to identifythe optimal route (e.g., most direct and/or unobstructed pathway) forthe medical procedure. A percutaneous cholecystoduodenostomy proceduremay involve placing a drainage stent between the gallbladder (e.g.,second body lumen) and duodenum (e.g., first body lumen) by followingthe same steps as those outlined above, with the exception that theneedle 110 of FIGS. 2A and 2B, is advanced from the gallbladder at anangle that bypasses the gastric wall and penetrates the duodenal wall(e.g., first tissue wall) and into the duodenum (not shown).Alternatively, a percutaneous cholecystojejunostomy procedure mayinvolve placing a drainage stent between the gallbladder (e.g., secondbody lumen) and jejunum (e.g., first body lumen) by following the samesteps as those outlined above, with the exception that the needle 110 ofFIGS. 2A and 2B, is advanced from the gallbladder at an angle thatbypasses the gastric wall and penetrates the jejunum wall (e.g., firsttissue wall) and into the jejunum (not shown).

A percutaneous gastroduodenostomy procedure may involve placing adrainage stent between the stomach (e.g., second body lumen) andduodenum (e.g., first body lumen) by advancing a needle through aportion of the peritoneal cavity prior to penetrating the stomach, andfurther advancing the needle through the duodenum wall (e.g., firsttissue wall) and into the duodenum (e.g., first body lumen).

A percutaneous gastrojejunostomy procedure may involve placing adrainage stent between the stomach (e.g., second body lumen) and jejunum(e.g., first body lumen) by advancing a needle through a portion of theperitoneal cavity prior to penetrating the stomach, and furtheradvancing the needle through the jejunum wall (e.g., first tissue wall)and into the jejunum (e.g., first body lumen).

A percutaneous gastroileostomy procedure may involve placing a drainagestent between the stomach (e.g., second body lumen) and ileum (e.g.,first body lumen) by advancing a needle through a portion of theperitoneal cavity prior to penetrating the stomach, and furtheradvancing the needle through the ileum wall (e.g., first tissue wall)and into the ileum (e.g., first body lumen).

A percutaneous choledochoduodenostomy procedure may involve placing adrainage stent between the common biliary duct (e.g., second body lumen)and duodenum (e.g., first body lumen) by advancing a needle through aportion of the peritoneal cavity prior to penetrating the common biliaryduct, and further advancing the needle through the duodenum wall (e.g.,first tissue wall) and into the duodenum (e.g., first body lumen).

A percutaneous enteroenterostomy procedure may involve placing adrainage stent between a first portion of the intestine (e.g., secondbody lumen) and a second portion of the intestine (e.g., first bodylumen) by advancing a needle through a portion of the peritoneal cavityprior to penetrating the first portion of the intestine, and furtheradvancing the needle through the intestine wall (e.g., first tissuewall) and into the second portion of the intestine (e.g., first bodylumen).

A percutaneous pseudocyst (e.g., walled-off pancreatic necrosis (WOPN),pancreatic fluid collection, etc.) or abscess procedure may involveplacing a drainage stent between the pseudocyst or abscess (e.g., secondbody lumen) and duodenum or stomach (e.g., first body lumen) byadvancing a needle through a portion of the peritoneal cavity prior topenetrating the pseudocyst or abscess, and further advancing the needlethrough the duodenum or stomach wall (e.g., first tissue wall) and intothe second portion of the duodenum or stomach (e.g., first body lumen).

A percutaneous external biliary drain conversion procedure may involveplacing a drainage stent between the gallbladder and stomach orduodenum, as described above. The biliary duct (e.g., common bile duct)may then be routed through the existing needle tract from thegallbladder to the skin to drain externally (e.g., into a collectionbag).

Although the systems and methods of the present disclosure include acombination of ultrasonic and/or fluoroscopic imaging modalities, invarious embodiments, the methods disclosed herein may be performed usingonly ultrasonic imaging. For example, certain patients may not beindicated for radiology procedures or are too sick to be transferred tothe radiology department. Alternatively, the medical institution may notbe fully equipped or staffed to support the fluoroscopy procedure.

The stent configuration depicted in FIGS. 3-7 is provided by way ofnon-limiting example, and may include a variety of different shapes,configurations, orientations, dimensions and/or materials as required toprovide a flow pathway between first and second body lumens, and in someexamples, appose adjacent tissue walls.

For example, stents for use with methods in various embodiments of thepresent disclosure may be self-expanding or balloon-expandable. Thestents may be formed from a suitable polymeric or metallic material. Inone embodiment, upon release from constraint within a stent deliverysystem, proximal and distal flanges may contact the respective innersurfaces of the first (e.g., gallbladder) and second (e.g., stomach)body lumens to place the tissue walls in apposition along aforeshortened saddle region that extends between the flanges of thestent. In another embodiment, the saddle region between the proximal anddistal flanges may not foreshorten, thereby maintaining a gap or spacebetween the first and second body lumens.

A porcine model was employed to test the safety and feasibility ofperforming an image guided, fully percutaneous, internal gallbladderdrainage procedure (e.g., cholecysto-enteric anastomosis) via endoscopicultrasound guided placement of a fully covered drainage stent. Theexperimental procedures were performed on seven 30 kg female white pigsunder general anesthesia and endotracheal intubation. A percutaneousthrough-and-through puncture of the gallbladder and into the stomach wasperformed using an 18-gauge needle under ultrasound and fluoroscopicguidance. A guidewire was then inserted through the lumen of the needleinto the stomach, and a 12 Fr sheath was inserted over the guidewireinto the gastric lumen. A 10 mm lumen apposing stent (e.g., AXIOS™stent, Boston Scientific, Marlborough, Mass.) was then percutaneouslydelivered over the wire and through the sheath. The sheath was retractedunder fluoroscopic and ultrasound visualization, to deploy the distalflange of the stent within the stomach and the proximal flange of thestent within the gallbladder. Contrast was then injected to confirmadequate placement of the stent and evaluate post-implantation leakage.Contrast injection demonstrated free flow through the stent with nocholecysto-enteric anastomotic leakage. All materials (e.g., the needle,sheath, guidewire, etc.) were then removed and the cholecysto-entericanastomosis was examined endoscopically and laparoscopically. Asubsequent necropsy of each animal confirmed appropriate stent positionand good apposition of the gallbladder and stomach, without injury tosurrounding structures. The technical success of each procedure was100%, with procedure times progressively decreasing for subsequentprocedures (e.g., 43 minutes, 27 minutes, 21 minutes, 18 minutes, 22minutes and 20 minutes). This experiment demonstrates the feasibilityand safety of an image guided, fully percutaneous, internal gallbladderdrainage procedure, in accordance with embodiments of the presentdisclosure, as a therapeutic option, e.g., in high risk patients, suchas patients with acute cholecystitis. The techniques according toembodiments of the present disclosure, including as described withrespect to the experiment, may represent an alternative to bothendoscopic ultrasound guided stent placement and/or externalpercutaneous cholecystostomy tube drainage.

Variations on these devices and other devices, and associated componentsand features which may be suitable for the systems and methods of thepresent disclosure, can be found in U.S. application Ser. Nos.14/186,994, 11/867,636 (issued as U.S. Pat. No. 8,425,539), Ser. No.12/427,215 (issued as U.S. Pat. No. 8,454,632) and Ser. No. 12/772,762(issued as U.S. Pat. No. 8,357,193), the entire disclosures of which areherein incorporated by reference in their entirety.

For example, the stent structures shown in FIGS. 8A-8D may be referredto as double-walled flange structures. FIG. 8A illustrates a stent 180with cylindrical saddle region 182 and a proximal and distal flange 181with a relatively large diameter open cylindrical region and a widediameter cuff or lip 183 on the flange structures 181. FIG. 8Billustrates a stent 180 with a smaller internal diameter than FIG. 8Abut with a larger diameter double-walled flange 181 for atraumaticallyengaging the tissue. FIG. 8C illustrates a stent 180 with an outer cuffor lip 183 diameter that is greater than the diameter of the internalcylindrical saddle region.

FIG. 8D illustrates an embodiment of a stent 180 similar to FIG. 8C butwith a eparate plug 184 in the flanges 181 to prevent food, fluids orother materials from getting stuck in the flange volume. The plug may bemade of a material that is suitable to flow or pass through thedigestive track after the stent is removed. In some embodiments, theflange may be made of a biodegradable or bioabsorbable material. Theflange plug structure can be used with any of the stent structuresdisclosed herein.

In some embodiments, the stent ends are symmetrical. In someembodiments, the stent ends can have different end shapes. The stent endshapes can be selected based on the body lumens and location of theanastomosis and desired physical properties. The stents can be designedto facilitate unidirectional flow, e.g., if food or partially digestedfood, or fluid or other material are intended to primarily flow in onedirection. The unidirectional flow can also exert or require additionalstrength for the leading stent flange (e.g., proximal flange) that firstcontacts the flow of material. The proximal flange can be designed witha cross-section that has a stronger pull-out force than the distalflange. The diameter of the opening in the proximal flange can have awider design than the distal flange to minimize the chances of materialgetting stuck within the flange. The ends of the proximal flange canalso be designed to further decrease the chances of getting food, fluidor other material stuck in the flange. For example, a stent could havethe cross-section illustrated in FIG. 10A for the proximal flange withits wider flange end and a flange design like FIG. 10I for the distalflange as illustrated in FIG. 10J, as shown below.

The dimensions of stents for use in various embodiments can be designedto provide a desired hold on the tissue walls along with a desiredconduit for fluid flow. For example, the width and diameter of a flangecan be optimized to provide the desired properties. A cuff or lip can beprovided distally to a flange to provide additional strength. Thediameter and length of a cuff can also be optimized to modify theproperties of stents. The diameter of a cuff can be greater than thediameter of the cylindrical hollow portion. This can make subsequentaccess to a stent easier and decrease the chance of material gettingstuck in the flange. The cuff or outer lip can also be shaped tominimize the chance of food, partially digested food, or other materialsgetting stuck within the flange volume. For example, an outer cuff orlip can include a wall that projects or curls away from the interiorvolume of the stent.

The diameter and length of a stent's cylindrical portion (sometimesreferred to as saddle region) can be optimized based on the thickness ofthe tissue walls and desired stent location. The overall length ofstents can also be optimized based on the specific application. Thesecond and third flanges may be separated by a third distance, the thirddistance being greater than the first distance. The flanges may includean outer diameter d₁ that is greater than an outer diameter d₂of thesaddle region. For example, outer diameter d₁ may be approximately 7.0mm to approximately 30 mm, and outer diameter d₂ may be approximately3.0 mm to approximately 15.0 mm. For example, in one or moreembodiments, the flanges may include an outer diameter d₁ that is asmuch as 75%-100% greater than an outer diameter d₂ of the cylindricalsaddle region.

Examples of manufacturing techniques for stents include using lasercutting, weaving, welding, etching, and wire forming. A membrane,coating or covering material such as silicone can be applied to an inneror outer surface of the wire stent frame to prevent the passage of fluidthrough the stent walls. The covering or coating may fully or partiallycover a stent frame. The membrane material can be applied by painting,brushing, spraying, dipping, or molding.

Although the flanges of FIGS. 8A-8D are depicted as extendingsubstantially perpendicular to the longitudinal axis of the cylindricalsaddle region, in various embodiments one, or both, of these flanges mayextend outward towards an end of the elongate body, back towards acenter portion of the elongate body, or change directions in somecombination of both at points of inflection along the flange as you movefrom the longitudinal axis to the ends of the flanges. The use of theterm “flange” and terms to describe the orientation of flanges withrespect to the longitudinal axis of a stent, are not intended to belimiting. For example, a flange may be said to extend, project,protrude, flare, point, or otherwise have an orientation at some degreeof angle from the longitudinal axis of a stent.

For example, an end or flange shape can be optimized to improve thestrength of a stent and to provide a sufficient amount of linear forceapposing and/or opposing each tissue plane while allowing smooth flow ofmaterial through the inner lumen opening of saddle regions. End shapescan be described as “bell-like,” consisting of multiple structuralfolds, having a plurality of inflection points, etc. The inflectionpoint can be considered a point of a curve at which a change in thedirection of curvature occurs. Additional ends might be rolled or mayprotrude retrograde against the tissue plane. Alternate designs mightconsist of a mouth that is wider than the inner diameter of the device.

As non-limiting examples of exemplary flange configuration. FIG. 9Aillustrates a cross-section of an embodiment of a stent 250 with acylindrical saddle region 251, flange 252 with an end 253 configured tobend back towards flange 254, flange 254 with an end 255 configured tobend back towards flange 252. The flanges 252, 254 and ends 253, 255 areconfigured to hold, maintain, or urge the tissue walls T1, T2 inapposition. The distal portion of the flanges 252, 254 are curved toreduce trauma to the tissue walls. FIGS. 9B and 9C have a similarconfiguration to FIG. 9A but with the ends 253, 255 of the stent furthercurled or curved. FIG. 9B shows the ends 253, 255 curled or curved inroughly a half circle and FIG. 9C has ends 253, 255 formingapproximately a full circle. The ends 253, 255 of the stents in FIGS.9B-C can atraumatically engage the tissue with increased strength fromthe additional curling on the distal ends of the stent structure.

FIGS. 9D-9G illustrate additional cross-sectional views of stentstructures. FIG. 9D illustrates a stent 250 with flange structures 252,254 projecting away from the cylindrical saddle region 251. Thecylindrical saddle region 251 has a diameter of D1 and the outer flangestructure 252, 254 has a larger diameter D2. FIG. 9E illustrates a stent250 with flange structures 252, 254 curling or curving outward and awayfrom the interior volume of the cylindrical saddle region 251. FIG. 9Fillustrates flange structures 252, 254 that project away from thecylindrical saddle region 251 and have curled or curved ends 253, 255.The curled or curved ends can provide additional lateral strength to thestent. FIG. 9G illustrates flange structures 252, 254 that project awayfrom the interior volume of the cylindrical saddle region 251 andfurther include double walled flange structures to increase the strengthof the stent 250 and to further engage atraumatically with tissue wallswhen implanted.

FIGS. 10A-10J illustrate a variety of partial cross-sections for stentflange configurations. Some flange structures can have a volume withineach flange that might trap food, fluid or other material passingthrough the stent. The flange can be designed to minimize the chance offood or other material getting trapped within the internal volume of thestent or stent flange. The stents illustrated in FIGS. 10A-10I haveflange structures that are designed to minimize food, partially digestedfood, or other materials getting trapped or stuck within the flangevolumes.

FIG. 10A illustrates a partial cross-section of a stent 260 with aflange structure 262 having a plurality of inflection points. Theinflection points create radial bends in the three-dimensional stentstructure. The flange 262 wall projects away from the cylindrical saddleregion 261 (a first inflection point) then bending back towards thecenter of the longitudinal pathway 264 of the stent 260 (two moreinflection points) followed by bending back again away from the centerof the longitudinal pathway 264 of the stent 260 (two more inflectionpoints) and an additional bend at the stent end 263 (one more inflectionpoint). Each of the bends can be considered an inflection point. Thestent 260 illustrated in FIG. 10A has 6 inflection points. Theinflection points can add additional strength to the stent flange. Thestent has an open end with a diameter that is greater than the diameterof the cylindrical saddle region 261 to reduce the likelihood of food,fluids or other materials getting stuck in the stent and to promote theflow of food, partially digested food, fluid and other materials throughthe stent body. The additional inflection point can increase the lateralstrength and pullout force of the expanded stent.

FIG. 10B illustrates a stent 260 with a flange structure 262 havingseven inflection points. The structure is similar to the stentillustrated in FIG. 10A but the outer stent wall angles back towards thecenter of the longitudinal pathway 264 at the end 263.

FIG. 10C illustrates a stent 260 with a flange structure 262 including acurled stent end 263. The curled end curls back towards the cylindricalsaddle region 261 forming a circular cross-section. The end 263 of thestent flange bends back towards itself so that the fluid flow does notflow directly at the end of the stent. This stent configuration furtherdecreases the likelihood food, fluids or other materials getting stuckwithin the internal volume of the flange 262.

FIG. 10D illustrates a stent 260 with a flange 262 projecting away fromthe longitudinal pathway 264 of the saddle region 261 and with an end263 curling or curving outwards past the outer point of the flange 262.

FIG. 10E illustrates a stent 260 with a flange 262 having fiveinflection points. The flange 262 projects outward away from the centerof the saddle region 261 and then bends back towards the center pathway264 followed by bending again with the end 263 projecting away from thelongitudinal center 264 of the cylindrical saddle region 261.

FIG. 1OF illustrates a stent 260 with a flange 262 projecting away fromthe cylindrical saddle region 261 and forming a curled circularcross-section with the end 263 curled or curved back towards the flange262.

FIG. 10G is similar to FIG. 1OF but with the circular end 263 curling orcurving to form greater than a full circle at the end 263 of the stent.

FIG. 10H illustrates a stent flange 262 having multiple bends resemblingright angles along with a curled end 263 curling away from thecylindrical center region 261. The right angles can increase the lateralstrength and pullout force of the stent.

FIG. 10I illustrates a flange having a sinusoidal outer shape with acurled end curling or curving away from the cylindrical saddle region.The wavy sinusoidal outer shape can increase the lateral strength andpullout force of the stent.

FIG. 10J illustrates a stent cross-section one a flange having thestructure illustrated in FIG. 10A and a flange illustrates in FIG. 10I.The flange illustrated in FIG. 10A has a wider opened and can bedeployed such that it faces the direction of fluid flow. The flangeillustrated in FIG. 10I has a narrower outer end and can be used as theopposing end where the material exits the internal volume of the stent.

All of the devices and/or methods disclosed and claimed herein can bemade and executed without undue experimentation in light of the presentdisclosure. While the devices and methods of this disclosure have beendescribed in terms of preferred embodiments, it may be apparent to thoseof skill in the art that variations can be applied to the devices and/ormethods and in the steps or in the sequence of steps of the methoddescribed herein without departing from the concept, spirit and scope ofthe disclosure. All such similar substitutes and modifications apparentto those skilled in the art are deemed to be within the spirit, scopeand concept of the disclosure as defined by the appended claims.

What is claimed is:
 1. A method of creating a passage between a firstbody lumen and a second body lumen for fluids to drain from the secondbody lumen to the first body lumen, said method comprising: extending astent having a first end and a second end into a second body lumen;extending the first end of the stent from the second body lumen to thefirst body lumen; deploying the first end of the stent in the first bodylumen; and after deploying the first end of the stent, deploying thesecond end of the stent in the second body lumen.
 2. The method of claim1, further comprising using a delivery system to deploy the first end ofthe stent in the first body lumen before deploying the second end of thestent in the second body lumen.
 3. The method of claim 2, furthercomprising: inserting the delivery system in a direction from the secondbody lumen to the first body lumen; and withdrawing the delivery systemin a direction from the first body lumen to the second body lumen. 4.The method of claim 1, further comprising percutaneously accessing thesecond body lumen and inserting the stent percutaneously into the secondbody lumen.
 5. The method of claim 4, further comprising advancing thestent within the body from the second body lumen to the first bodylumen.
 6. The method of claim 1, further comprising establishing adrainage passage from the second body lumen to the first body lumen. 7.The method of claim 1, further comprising creating an open flow passagefrom the second body lumen to the first body lumen.
 8. The method ofclaim 1, further comprising: expanding the first end of the stent withinthe first body lumen to deploy the first end of the stent within thefirst body lumen; and expanding the second end of the stent within thesecond body lumen to deploy the second end of the stent within thesecond body lumen.
 9. The method of claim 8, comprising expanding thefirst end of the stent within the first body lumen before expanding thesecond end of the stent within the second body lumen.
 10. The method ofclaim 1, wherein: deploying the first end of the stent comprisesdeploying the first end of the stent in a stomach; and deploying thesecond end of the stent comprises deploying the second end of the stentin a gall bladder.
 11. A method of creating a passage between a firstbody lumen and a second body lumen, wherein fluid flows in the body in adirection from the second body lumen to the first body lumen, saidmethod comprising: percutaneously inserting a stent having a first endand a second end into the second body lumen; advancing the first end ofthe stent from the second body lumen into the first body lumen;deploying the first end of the stent in the first body lumen; anddeploying the second end of the stent in the second body lumen toestablish directional fluid flow from the second body lumen into thefirst body lumen.
 12. The method of claim 11, further comprising:expanding the first end of the stent within the first body lumen todeploy the first end of the stent within the first body lumen; andexpanding the second end of the stent within the second body lumen todeploy the second end of the stent within the second body lumen.
 13. Themethod of claim 12, further comprising using a delivery system to deploythe first end of the stent in the first body lumen before deploying thesecond end of the stent in the second body lumen.
 14. The method ofclaim 13, further comprising: inserting the delivery system in adirection from the second body lumen to the first body lumen; andwithdrawing the delivery system in a direction from the first body lumento the second body lumen.
 15. The method of claim 11, wherein advancingthe first end of the stent from the second body lumen into the firstbody lumen comprises advancing the first end of the stent within thebody.
 16. A method of establishing a temporary flow passage between afirst body lumen and a second body lumen, said method comprising:deploying a stent in a direction from the second body lumen to the firstbody lumen to deploy a first end of the stent in the first body lumenbefore deploying the second end of the stent in the second body lumen;and withdrawing the stent in a direction from the second body lumen tothe first body lumen.
 17. The method of claim 16, further comprisingestablishing a drainage passage from the second body lumen to the firstbody lumen.
 18. The method of claim 16, further comprisingpercutaneously inserting the stent into the second body passage and thenadvancing the stent within the body to the first body passage.
 19. Themethod of claim 18, further comprising removing the stent through ascope inserted in a natural body orifice.
 20. The method of claim 16,wherein: deploying the first end of the stent comprises deploying thefirst end of the stent in a stomach; and deploying the second end of thestent comprises deploying the second end of the stent in a gall bladder.